Repairing components of refrigerant circuit of 2nd heater and air conditioning unit “4-C” — VW

Repairing components of refrigerant circuit of 2nd heater and air conditioning unit
“4-C”
Special tools and workshop equipment required
Air conditioner service station
Note
The refrigerant circuit must be purged with refrigerant R134a:
If dirt or other contamination is in the circuit.
If during the evacuation of a leak-tight refrigerant circuit the vacuum is not maintained at the gauge (there is moisture in the refrigerant circuit and this generates vapour pressure).
If the refrigerant circuit has been left open for longer than normally required for repairs (e.g. following an accident).
When pressure and temperature measurements in the refrigerant circuit indicate that there is moisture in the refrigerant circuit.
There is doubt about the amount of refrigerant oil in the refrigerant circuit.
The air conditioner compressor has to be exchanged because of internal damage (e.g. noisy or lack of power).
The procedure for purging can be found in the workshop manual
“Air conditioning system with refrigerant R134a VW”
Rep. gr.
00
, Technical data, Clearing refrigerant circuit of contaminants.
Note
The refrigerant must be extracted beforehand, with the
air conditioning service station
.
Releasing refrigerant into the environment is a punishable offence.
The previously used air conditioner service stations can still be used ⇒ Volkswagen Workshop Equipment catalogue.
Safety measures when working with an extracted refrigerant circuit
Chapter
. Notes on repair work to vehicles with air conditioning and on handling refrigerant.
To prevent the intrusion of moisture, all components of the refrigerant circuit which have been opened must be sealed with suitable plugs.
The colour coding of O-rings for R134a refrigerant circuits has been discontinued. Coloured and black O-rings are used.
Under certain conditions, it is not necessary to renew the dryer cartridge every time that the refrigerant circuit is opened. Refer to workshop manual
“Air conditioning system with refrigerant R134a”
Rep. gr.
00
“Technical data”
; Renewing components.
Refrigerant line
High-pressure side.
Beneath rear left wheel housing liner.
O-ring
Renew
9.5 mm; 2.5 mm
O-ring
Renew.
13.7 mm; 2.5 mm
Socket head bolt with washer M8x28
12 Nm ±1 Nm
Qty. 2
Refrigerant line
Low-pressure side
Beneath rear left wheel housing liner.
Socket head bolt with washer M6x35
3.5 Nm ±0.5 Nm
Socket head bolt with washer M6x35
3.5 Nm ±0.5 Nm
Socket head bolt with washer M6x70
3.5 Nm ±0.5 Nm
Socket head bolt with washer M6x70
3.5 Nm ± 0.5 Nm
O-ring
Renew.
13.7 mm; 2.5 mm
O-ring
Renew.
9.5 mm; 2.5 mm
Refrigerant line
Low-pressure side
On vehicle underbody.
Refrigerant line
High-pressure side.
On vehicle underbody.
Bolt M6x16
8 Nm ±1.2 Nm
Ancillary bracket
Bolt M6x16
8 Nm ±1.2 Nm
Spacer
Socket head bolt with washer M6x35
3.5 Nm ±0.5 Nm
Socket head bolt with washer M6x35
3.5 Nm ±0.5 Nm
Damper
O-ring
Renew
9.5 mm; 2.5 mm
Socket head bolt with washer M8x28
12 Nm ±1 Nm
Refrigerant line
High-pressure side.
Beneath front left wheel housing liner.
O-ring
Renew
13.7 mm; 2.5 mm
Socket head bolt with washer M8x28
12 Nm ±1 Nm
Refrigerant line
Low-pressure side
Beneath front left wheel housing liner.